I have looked for a delrin example of mcmaster part number 1710K4 but have had no luck. Closest I came was a guy on ebay selling 1/2-10, but that won't work for my application, I need the speed of a 5 thread.

Thanks,

If you haven't already purchased the screws consider a 1/2"-10 acme (2 start) which gives you 5 turns per inch.. and resonable cost anti backlash nuts are available from dumpstercnc.com I went with the 1/2"-8 (2 start) to get 4 turns per inch and it works very very well, and dumpstercnc has a full line of couplers and collars to work with those screws. I have no tie to dumpstercnc, it's just a good product and saved me alot of time and headache with my build so I'd happily recommend them to anyone.

Try roton.com, they have it.
http://www.roton.com/QS_lead.aspx?line=Quick

regards

Price around on size, number of starts and nut availability before you buy anything. Some anti-backlash nuts get real pricey. Some screw-nut combinations are harder to find. I think that's one reason so many people opt for the 1/2x10 single start for their first build.
John